This week will be the last week of Daily Vitamins until Monday, September 12.

We will finish the year with a series of four Daily Vitamins with expressions that use the English word LIGHT in them. On Friday, in the Essential Weekly Vitamin, we will give you some tips for keeping your English strong in the summer.

Today's expression is: to be or go out like a light (informal)

Meaning: to go to sleep very quickly.

Example 1: I began to read the story to my son, but he was out like a light after 3 minutes. He must have been very tired.

Example 2: She always goes out like a lightwhen she travels by plane, but I can never seem to sleep when I fly.

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